A prior art trapped flux, magnet iron structure is described in U.S. Pat. No. 4,917,736, which was issued on Apr. 17, 1990 to the same inventor as the inventor of this application, which is incorporated herein by reference. The prior art magnet iron structure includes an inner portion made of a soft ferromagnetic material and an outer portion made of a superconductive sheath. This magnet iron structure traps enhanced flux in the soft ferromagnetic inner portion by the enclosing outer superconductive sheath.
One problem with the prior art trapped flux, magnet iron structure is that it is difficult to trap flux, which is directed in different directions in different parts of a complex arrangement.
Another problem with the prior art trapped flux, magnet iron structure is that the flux is only trapped by the sheath, and is free to wander and bunch within the boundary of the sheath or the superconductive bounded region, which causes a "sponginess" of force, and reaction, and torque, in various applications.
One object of the present invention is to provide a trapped flux, magnet iron structure, which has an improved flux distribution.
Another object is to provide a trapped flux, magnet iron structure which is not difficult to use in a complex arrangement or application, and which does not have a "sponginess" in its force and reaction and torque in an application.